A thick, swirling school of blackfin barracuda plies the blue waters off Sipadan Island, Malaysia. The fish are formidable predators, but they sometimes gather in groups for protection against sharks higher up on the food chain..
The sweeping color of sea and sky, blue is a common thread in nature, seen in the cerulean of a whale shark (pictured here), the indigo of a stormy night, and the cobalt of a peacock's feathers. Over the centuries, the hue has come to represent calm, cold, mysticism, and sadness
A group of chinstrap penguins lines the edge of an iceberg adrift in Antarctic waters. Chinstraps are among the most abundant penguins, and some colonies live on floating icebergs.
A blue pool on Root Glacier in Alaska's Wrangell-St. Elias National Park reflects the bulk of towering Donoho Peak. The massive ice sheet is a popular excursion in the park.
These distinctive webbed feet belong to a blue-footed booby of the Galápagos Islands. The bluer, the better: Courting males show off with a high-stepping strut—and those with brighter feet are more attractive to potential mates.
Frost covers the brilliant blue leaves of lush ferns in New Zealand's Fiordland National Park. The park is an isolated wilderness that's home to more than 700 plants found nowhere else in the world.
Unveiling the regalia that has captivated humans (and hens) for thousands of years, an Indian peacock displays his colorful train at an Australian reserve. Males may use their feathers to attract harems of several hens.
As startling as a bright-blue eye, a central lagoon peers out from Rocas Baimbridgen in Ecuador's Galápagos Islands. The stark, rocky island teems with life at times—the brackish lagoon waters are favored by flamingos.
The massive bulk of Garibaldi Glacier slowly spills into Garibaldi Fjord in Tierra del Fuego—the archipelago at the southern tip of South America. The aquatic endpoint of such a glacier is known as a terminus.